Hitachi Predicts Solar Output Fluctuations Based on Cloud Movements

2014/04/02 08:48

Kiyotaka Nakanishi, Nikkei BP CleanTech Institute

Hitachi Industry & Control Solutions Ltd announced March 27, 2014, that it has developed a technology to predict the output fluctuation of solar panels with a high accuracy in almost real time based on cloud movements.

Hitachi Industry & Control Solutions is a company based in Hitachi City, Ibaraki Prefecture, Japan, and develops production management systems.

The output power of a solar power generation system sometimes sharply fluctuates in a short time. Especially, when clouds are moving fast and intermittently blocking sunlight on a cloudy day, the sharp fluctuation of the output affects the grid system. When a solar power generation system with a large capacity is connected to a grid system, it is necessary to prevent a rapid fluctuation of output.

This time, Hitachi Industry & Control Solutions developed an algorithm that predicts cloud movements based on the pictures of the sky taken at intervals of several seconds. The fluctuation of output can be predicted by calculating what will be the positional relation between the sun and clouds several seconds later based on the images of the sky above solar panels. By controlling the charge/discharge of a storage battery system in sync with the predicted fluctuation, it becomes possible to prevent rapid output fluctuation, the company said.

Hitachi Industry & Control Solutions aims to further improve the prediction accuracy while dealing with a wider variety of weather conditions.